Question

Bilaterally symmetrical and acoelomate animals are found in which phylum ?

• A. Platyhelminthes
• B. Aschelminthes
• C. Annelida
• D. Ctenophora

Answer 1

Answer:

A. Platyhelminthes

• Bilaterally symmetrical and acoelomate animals are found in the phylum Platyhelminthes.

Explanation:

• Platyhelminthes (flatworms) are characterized by being bilaterally symmetrical (their body can be divided into two mirror-image halves) and acoelomate (lacking a true body cavity or coelom).

• Aschelminthes (roundworms) are bilaterally symmetrical, but they are pseudocoelomate, meaning they have a false body cavity.

• Annelida (segmented worms) are bilaterally symmetrical and coelomate, possessing a true body cavity.

• Ctenophora (comb jellies) are radially symmetrical and acoelomate.